Scheduling requests for grant-free configurations

ABSTRACT

Generally, the described techniques provide for a user equipment (UE) generating a scheduling request (SR) for a set of data for an uplink transmission from the UE to a base station. The UE may determine whether the SR for the set of data is associated with a grant-free configuration for the UE. The grant-free configuration may indicate a set of time-frequency resources that the UE may use to transmit the set of data. The UE may transmit to the base station an indication of whether the SR is associated with the grant-free configuration. If the SR is associated with a grant-free configuration for the UE, the UE may use the corresponding resources to transmit the set of data to the base station, and the base station may then decode the data based on having received the indication of the resources by way of the grant-free configuration.

CROSS REFERENCE

The present Application for Patent claims benefit of U.S. ProvisionalPatent Application No. 62/670,654 by SUNDARARAJAN et al., entitled“Scheduling Requests For Grant-Free Configurations,” filed May 11, 2018,assigned to the assignee hereof, and expressly incorporated by referenceherein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to scheduling requests (SRs) for grant-free configurations.

Wireless communications systems are widely deployed to provide varioustypes of communications content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code-division multiple access (CDMA), time-divisionmultiple access (TDMA), frequency-division multiple access (FDMA),orthogonal frequency-division multiple access (OFDMA), or discreteFourier transform-spread-orthogonal frequency-division multiplexing(DFT-s-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationsdevices, which may be otherwise known as user equipment (UE).

A wireless communications system may utilize a grant-based transmissionscheme where, for example, a UE requests time-frequency resources forperforming an uplink transmission. A UE may request such resources bytransmitting an SR to a base station. Some wireless communicationssystems may support a grant-free transmission scheme in whichtime-frequency resources are allocated to one or more UEs, and UEs mayutilize these resources for uplink transmission without transmitting anSR. Communications systems that support grant-free transmission schemesand SRs may result in miscommunications, excessive communications, orother issues.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support scheduling requests (SRs) for grant-freeconfigurations in wireless communications systems. Generally, thedescribed techniques provide for a user equipment (UE) utilizing an SRfor transmission of a set of data, which may be associated with agrant-free configuration. The grant-free configuration may indicate aset of grant-free time-frequency resources that the UE may use totransmit data without receiving a grant. In some cases, the UE maytransmit to the base station an indication of whether the SR isassociated with the grant-free configuration. For example, if the SR isassociated with a grant-free configuration, the UE may use thecorresponding resources to transmit the set of data to the base station,and the base station may then decode the data. The base station may alsoassociate the SR transmitted by the UE with the decoded set of data andeither disregard the SR if the data has already been decoded, or monitorthe grant-free configuration indicated by the SR to receive and decodethe data. Alternatively, if the SR is associated with a grant-freeconfiguration, the base station may transmit an uplink grant to the UEindicating a set of resources for the UE to use for transmission of thedata.

A method of wireless communications is described. The method may includegenerating an SR for a set of data for an uplink transmission from a UEto a base station and determining whether the SR for the set of data isassociated with a grant-free configuration for the UE. The method mayinclude transmitting, to the base station, an indication of whether theSR is associated with the grant-free configuration based on thedetermination.

An apparatus for wireless communications is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to generate an SRfor a set of data for an uplink transmission from a UE to a base stationand determine whether the SR for the set of data is associated with agrant-free configuration for the UE. The instructions may be executableby the processor to cause the apparatus to transmit, to the basestation, an indication of whether the SR is associated with thegrant-free configuration based on the determination.

Another apparatus for wireless communications is described. Theapparatus may include means for generating an SR for a set of data foran uplink transmission from a UE to a base station and means fordetermining whether the SR for the set of data is associated with agrant-free configuration for the UE. The apparatus may include means fortransmitting, to the base station, an indication of whether the SR isassociated with the grant-free configuration based on the determination.

A non-transitory computer-readable medium storing code for wirelesscommunications is described. The code may include instructionsexecutable by a processor to generate an SR for a set of data for anuplink transmission from a UE to a base station and determine whetherthe SR for the set of data is associated with a grant-free configurationfor the UE. The code may include instructions executable by theprocessor to transmit, to the base station, an indication of whether theSR is associated with the grant-free configuration based on thedetermination.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the indicationmay include operations, features, means, or instructions fortransmitting the SR to the base station, where the SR indicates whetherthe SR may be associated with the grant-free configuration.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the SR mayinclude operations, features, means, or instructions for identifying aspreading sequence that indicates information associated with thegrant-free configuration and transmitting the SR according to thespreading sequence. Some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein may furtherinclude operations, features, means, or instructions for identifying acodeword that indicates information associated with the grant-freeconfiguration and transmitting the SR, where the SR includes thecodeword. Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a cyclicredundancy check (CRC) mask corresponding to information associated withthe grant-free configuration and transmitting the SR based on the CRCmask.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the SR indicates that the SRmay be associated with the grant-free configuration and the SR indicatesa indicates a radio access technology (RAT), a carrier, an index of thegrant-free configuration, or a combination thereof. In some examples ofthe method, apparatuses, and non-transitory computer-readable mediumdescribed herein, the SR indicates that the SR may be not associatedwith the grant-free configuration.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the SR tothe base station, where the SR may be not associated with the grant-freeconfiguration for the UE, receiving, from the base station, a grant thatindicates a set of time-frequency resources for the uplink transmissionand transmitting the uplink transmission to the base station via the setof time-frequency resources.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the SR tothe base station, where the SR may be associated with the grant-freeconfiguration for the UE, identifying a set of time-frequency resourcesbased on the grant-free configuration, and transmitting the uplinktransmission to the base station via the set of time-frequencyresources.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the uplink transmission andthe SR may be transmitted on different carriers. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, the uplink transmission and the SR may be transmittedusing different RATs.

A method of wireless communications is described. The method may includeidentifying, by a base station, a set of grant-free configurations for aUE, and receiving, from the UE, an SR associated with an uplinktransmission from the UE to the base station, where the SR indicateswhether the SR is associated with a grant-free configuration of the setof grant-free configurations. The method may include transmitting adownlink transmission to the UE based on the SR, where the downlinktransmission includes a feedback message, an uplink grant, or acombination thereof.

An apparatus for wireless communications is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to identify, by abase station, a set of grant-free configurations for a UE, and receive,from the UE, an SR associated with an uplink transmission from the UE tothe base station, where the SR indicates whether the SR is associatedwith a grant-free configuration of the set of grant-free configurations.The instructions may be executable by the processor to cause theapparatus to transmit a downlink transmission to the UE based on the SR,where the downlink transmission includes a feedback message, an uplinkgrant, or a combination thereof.

Another apparatus for wireless communications is described. Theapparatus may include means for identifying, by a base station, a set ofgrant-free configurations for a UE and means for receiving, from the UE,an SR associated with an uplink transmission from the UE to the basestation, where the SR indicates whether the SR is associated with agrant-free configuration of the set of grant-free configurations. Theapparatus may include means for transmitting a downlink transmission tothe UE based on the SR, where the downlink transmission includes afeedback message, an uplink grant, or a combination thereof.

A non-transitory computer-readable medium storing code for wirelesscommunications is described. The code may include instructionsexecutable by a processor to identify, by a base station, a set ofgrant-free configurations for a UE, and receive, from the UE, an SRassociated with an uplink transmission from the UE to the base station,where the SR indicates whether the SR is associated with a grant-freeconfiguration of the set of grant-free configurations. The code mayinclude instructions executable by the processor to transmit a downlinktransmission to the UE based on the SR, where the downlink transmissionincludes a feedback message, an uplink grant, or a combination thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that the SRmay be associated with the grant-free configuration and decoding atransmission from the UE transmitted over a set of time-frequencyresources associated with the grant-free configuration.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a spreadingsequence associated with the SR, where the spreading sequence indicatesinformation associated with the grant-free configuration. Some examplesof the method, apparatuses, and non-transitory computer-readable mediumdescribed herein may further include operations, features, means, orinstructions for identifying a codeword of the SR, where the codewordindicates information associated with the grant-free configuration. Someexamples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining a CRC maskof the SR, where the CRC mask corresponds to information associated withthe grant-free configuration.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the SR indicates a RAT, acarrier, an index of the grant-free configuration, or a combinationthereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to theUE, a Radio Resource Control (RRC) message or a medium access control(MAC) control element (CE) that indicates information to convey via theSR.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that the SRmay be not associated with the grant-free configuration and transmittingthe feedback message or the uplink grant based on determining that theSR may be not associated with the grant-free configuration.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the uplinktransmission from the UE based on the SR. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, the uplink transmission and the SR may be received ondifferent carriers. In some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein, the uplinktransmission and the SR may be received using different RATs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system inaccordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system inaccordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a process flow in accordance withaspects of the present disclosure.

FIGS. 4 and 5 show block diagrams of devices in accordance with aspectsof the present disclosure.

FIG. 6 shows a block diagram of a communications manager in accordancewith aspects of the present disclosure.

FIG. 7 shows a diagram of a system including a device in accordance withaspects of the present disclosure.

FIGS. 8 and 9 show block diagrams of devices in accordance with aspectsof the present disclosure.

FIG. 10 shows a block diagram of a communications manager in accordancewith aspects of the present disclosure.

FIG. 11 shows a diagram of a system including a device in accordancewith aspects of the present disclosure.

FIGS. 12 through 19 show flowcharts illustrating methods in accordancewith aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communications systems may utilize a grant-basedtransmission scheme to indicate time-frequency resources on which a userequipment (UE) or a base station may transmit data. In grant-baseduplink operation, a UE that has data to transmit may transmit ascheduling request (SR) to a base station, and the base station mayreply to the UE with an uplink grant indicating resources on which totransmit the data. The UE may then use the assigned resources totransmit the data. This grant-based uplink operation, however, incurs adelay from the time at which data becomes available at the UE totransmit and the time at which the UE transmits the data on the assignedresources.

To help reduce latency and signaling overhead associated with exchangingthe SR and the grant, a grant-free mode of uplink operation may be used.In the grant-free mode of uplink operation, the UE may be configuredwith one or more patterns of resources for a set of channels on whichthe UE may transmit data without having first received an uplink grant.In some cases, however, the network may not detect the data transmissionfrom the UE on these resources, in which case the data may not bedecoded and because there may be no mechanism for the UE to indicatethat a transmission has occurred, the base station may not send feedbackto indicate a decoding failure. Further, in some cases, the pattern ofresources to be used for grant-free transmissions may be preconfigured,in which case the resources may not be optimized for the current channeland interference conditions.

One technique for mitigating some of the drawbacks associated withgrant-based uplink operation and with grant-free uplink operation is forthe UE to transmit an SR in conjunction with (e.g., before,simultaneously with, or after) a grant-free data transmission. Accordingto this technique, when the data transmission is received and decoded(e.g., by a base station), the SR may be ignored and therefore does notcause a delay in transmission as a result of exchanging thetransmission. When the transmission is not detected and decoded (e.g.,because of a collision on a contention-based channel, or for otherreasons), the base station may use the SR as a trigger to decode thegrant-free transmission. Additionally or alternatively, for example, ifdecoding fails, the base station may use the SR to provide atransmission grant (or transmit feedback) indicating resources forretransmission of the data transmission. Thus, the latency of thetransmission may be decreased under some scenarios.

In some cases, the UE may be configured with a set of more than onegrant-free uplink configurations (e.g., grant-free uplink configurationscorresponding to different grant-free resources on one or morechannels). The UE may select one or more configurations from the set ofgrant-free uplink configurations with which to transmit. According tothis described technique, however, the base station may be unaware ofwhether to associate the SR with a grant-free uplink configuration, andif so, which grant-free uplink configuration (e.g., which grant-freeresources to decode). Without this knowledge, the base station mayblindly decode all possible configured resources, which may increasecomplexity.

According to aspects of the present disclosure, the UE may signalinformation to the base station to identify which particular grant-freeuplink resources to decode and whether a given SR is associated with agrant-free configuration. For example, the UE may embed informationwithin an SR that the base station may use to identify whether the SR isassociated with a grant-free uplink configuration, and if the SR isassociated with a grant-free uplink configuration, the particulargrant-free uplink configurations of a set of grant-free uplinkconfigurations with which to associate the SR. In some cases, the basestation may not provide an uplink grant in response to the SR if thebase station detects and decodes the associated grant-free transmissionsuccessfully. When the base station receives the SR according to thesetechniques, the base station may identify one or more grant-free uplinkconfigurations with which the SR is associated, and accordingly maydetermine which particular resources to decode.

The described technique may be used across different carriers and radioaccess technologies (RATs). For example, the UE may transmit thegrant-free data transmission on a first carrier or using a first RAT andtransmit the SR on a second carrier or using a second RAT (e.g., acarrier or RAT that uses a lower radio frequency spectrum band ascompared to the carrier or RAT used for the data transmission).Transmitting the SR on a lower radio frequency spectrum band withrelatively improved coverage and signal quality may provide forincreased reliability and thus a higher probability that the SR isdetected.

Aspects of the disclosure are initially described in the context of awireless communications system. Further examples illustrate a processflow for signaling indication as to whether an SR is associated with agrant-free uplink configuration, and if so, a particular grant-freeuplink configuration with which the SR is associated. Aspects of thedisclosure are further illustrated by and described with reference toapparatus diagrams, system diagrams, and flowcharts that relate toscheduling requests for grant-free configurations.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A)network, an LTE-A Pro network, or a New Radio (NR) network. In somecases, wireless communications system 100 may support enhanced broadbandcommunications, ultra-reliable (e.g., mission critical) communications,low latency communications, or communications with low-cost andlow-complexity devices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation Node B orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up only a portion of the geographic coverage area110, and each sector may be associated with a cell. For example, eachbase station 105 may provide communication coverage for a macro cell, asmall cell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving “deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 MHz to 300 GHz.Generally, the region from 300 MHz to 3 GHz is known as the ultra-highfrequency (UHF) region or decimeter band, since the wavelengths rangefrom approximately one decimeter to one meter in length. UHF waves maybe blocked or redirected by buildings and environmental features.However, the waves may penetrate structures sufficiently for a macrocell to provide service to UEs 115 located indoors. Transmission of UHFwaves may be associated with smaller antennas and shorter range (e.g.,less than 100 km) compared to transmission using the smaller frequenciesand longer waves of the high frequency (HF) or very high frequency (VHF)portion of the spectrum below 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that can tolerate interference from otherusers.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a CA configurationin conjunction with CCs operating in a licensed band (e.g., LAA).Operations in unlicensed spectrum may include downlink transmissions,uplink transmissions, peer-to-peer transmissions, or a combination ofthese. Duplexing in unlicensed spectrum may be based onfrequency-division duplexing (FDD), time-division duplexing (TDD), or acombination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving devices are equipped with one ormore antennas. MIMO communications may employ multipath signalpropagation to increase the spectral efficiency by transmitting orreceiving multiple signals via different spatial layers, which may bereferred to as spatial multiplexing. The multiple signals may, forexample, be transmitted by the transmitting device via differentantennas or different combinations of antennas. Likewise, the multiplesignals may be received by the receiving device via different antennasor different combinations of antennas. Each of the multiple signals maybe referred to as a separate spatial stream, and may carry bitsassociated with the same data stream (e.g., the same codeword) ordifferent data streams. Different spatial layers may be associated withdifferent antenna ports used for channel measurement and reporting. MIMOtechniques include single-user MIMO (SU-MIMO) where multiple spatiallayers are transmitted to the same receiving device, and multiple-userMIMO (MU-MIMO) where multiple spatial layers are transmitted to multipledevices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionor reception by the base station 105. Some signals, such as data signalsassociated with a particular receiving device, may be transmitted by abase station 105 in a single beam direction (e.g., a directionassociated with the receiving device, such as a UE 115). In someexamples, the beam direction associated with transmissions along asingle beam direction may be determined based on a signal that wastransmitted in different beam directions. For example, a UE 115 mayreceive one or more of the signals transmitted by the base station 105in different directions, and the UE 115 may report to the base station105 an indication of the signal it received with a highest signalquality, or an otherwise acceptable signal quality. Although thesetechniques are described with reference to signals transmitted in one ormore directions by a base station 105, a UE 115 may employ similartechniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115), or transmitting a signal in asingle direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples, areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based on listeningaccording to different receive beam directions (e.g., a beam directiondetermined to have a highest signal strength, highest signal-to-noiseratio, or otherwise acceptable signal quality based on listeningaccording to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may, insome cases, perform packet segmentation and reassembly to communicateover logical channels. A Medium Access Control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use hybrid automatic repeat request(HARQ) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and a base station 105 or corenetwork 130 supporting radio bearers for user plane data. At thePhysical (PHY) layer, transport channels may be mapped to physicalchannels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an Evolved UniversalTerrestrial Radio Access (E-UTRA) absolute radio frequency channelnumber (EARFCN)), and may be positioned according to a channel rasterfor discovery by UEs 115. Carriers may be downlink or uplink (e.g., inan FDD mode), or be configured to carry downlink and uplinkcommunications (e.g., in a TDD mode). In some examples, signal waveformstransmitted over a carrier may be made up of multiple sub-carriers(e.g., using multi-carrier modulation (MCM) techniques such asorthogonal frequency-division multiplexing (OFDM) or discrete Fouriertransform-spread-OFDM (DFT-s-OFDM).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR,etc.). For example, communications over a carrier may be organizedaccording to TTIs or slots, each of which may include user data as wellas control information or signaling to support decoding the user data. Acarrier may also include dedicated acquisition signaling (e.g.,synchronization signals or system information, etc.) and controlsignaling that coordinates operation for the carrier. In some examples(e.g., in a carrier aggregation configuration), a carrier may also haveacquisition signaling or control signaling that coordinates operationsfor other carriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time-divisionmultiplexing (TDM) techniques, frequency-division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples, the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or resource blocks (RBs)) within a carrier (e.g., “in-band”deployment of a narrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 or UEs 115 that can support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation (CA) or multi-carrier operation. A UE 115 may beconfigured with multiple downlink CCs and one or more uplink CCsaccording to a carrier aggregation configuration. Carrier aggregationmay be used with both FDD and TDD component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than otherCCs, which may include use of a reduced symbol duration as compared withsymbol durations of the other CCs. A shorter symbol duration may beassociated with increased spacing between adjacent subcarriers. Adevice, such as a UE 115 or base station 105, utilizing eCCs maytransmit wideband signals (e.g., according to frequency channel orcarrier bandwidths of 20, 40, 60, 80 MHz, etc.) at reduced symboldurations (e.g., 16.67 microseconds). A TTI in eCC may consist of one ormultiple symbol periods. In some cases, the TTI duration (that is, thenumber of symbol periods in a TTI) may be variable.

Wireless communications systems such as an NR system may utilize anycombination of licensed, shared, and unlicensed spectrum bands, amongothers. The flexibility of eCC symbol duration and subcarrier spacingmay allow for the use of eCC across multiple spectrums. In someexamples, NR shared spectrum may increase spectrum utilization andspectral efficiency, specifically through dynamic vertical (e.g., acrossthe frequency domain) and horizontal (e.g., across the time domain)sharing of resources.

In some examples, UE 115 transmits an SR in parallel with a grant-freedata transmission. These transmissions may, but in some cases may notbe, simultaneous. According to this technique, when the datatransmission is received and decoded (e.g., by a base station 105), theSR may be ignored and therefore does not result in delay due to the SR.When the transmission is not detected and decoded (e.g., because of acollision on a contention-based channel, or for other reasons), the basestation 105 may use the SR as a trigger to decode the grant-freetransmission. Additionally or alternatively, for example, if decodingfails, the base station 105 may use the SR to provide a transmissiongrant indicating resources for retransmission of the data transmission.Thus, the latency of the transmission may be decreased under somescenarios.

According to aspects of the present disclosure, the UE 115 may signalthis information to the base station 105 to identify which particulargrant-free uplink resources to decode. For example, the UE 115 mayinclude in the SR an indication as to whether the SR is associated witha grant-free uplink configuration, and if so, which particulargrant-free uplink configuration the SR is associated. In some cases, thebase station 105 may determine not to provide an uplink grant inresponse to the SR if the base station 105 detects and decodes theassociated grant-free transmission successfully. The described techniquemay be used across different carriers and RATs. For example, the UE 115may transmit the grant-free data transmission on a first carrier orusing a first RAT and transmit the SR on a second carrier or using asecond RAT (e.g., a carrier or RAT that uses a lower radio frequencyspectrum band as compared to the carrier or RAT used for the datatransmission). Transmitting the SR on a lower radio frequency spectrumband with relatively improved coverage and signal quality may providefor increased reliability and thus a higher probability that the SR isdetected.

FIG. 2 illustrates an example of a wireless communications system 200 inaccordance with aspects of the present disclosure. The wirelesscommunications system 200 includes a base station 105-a and a UE 115-a,which may be examples of the corresponding devices as described withreference to FIG. 1. The wireless communications system 200 may be anexample of a system that supports mmW communications. The wirelesscommunications system 200 may utilize signaling techniques fortransmitting and receiving SRs 205 to indicate grant-free configurationsfor transmitted and received uplink transmissions 210 between the UE115-a and the base station 105-a. In the below examples, a particularoperation may be described with reference to a UE 115 or a base station105, but it should be understood that the operation may also beperformed by either a UE 115 or a base station 105. Similarly, thegrant-free configurations may be described with reference to grant-freeuplink configuration, but it should be understood that analogousoperations may be applied for the downlink.

In some examples, the UE 115-a may be configured with one or moregrant-free configurations (e.g., one or more configured grants). Agrant-free configuration or a configured grant may be semi-staticallyconfigured via RRC signaling, or other signaling techniques, from a basestation 105-a, rather than being configured dynamically via controlsignaling (e.g., using a dynamically signaled grant in a physicaldownlink control channel (PDCCH)). A grant-free configuration mayindicate a set of time-frequency resources of a channel (e.g., a patternof time-frequency resources, a periodic set of frequency resources, andaperiodic set of frequency resources) configured for the UE 115-a to usefor autonomous uplink transmissions, as described in more detail below.Thus, the UE 115-a may use the set of resources indicated by thegrant-free configuration to transmit an uplink message (an uplink datatransmission, control information, etc.) to one or more devices (e.g.,base station 105-a) in the wireless communications system 200. The UE115-a may transmit this uplink message without receiving an additional,explicit uplink grant (e.g., from base station 105-a) for the set oftime-frequency resources. That is, the UE 115-a may transmit the uplinkmessage over these resources without having to schedule the uplinkmessage (e.g., through transmission of an SR to base station 105-a). Inthis manner, the UE 115-a may autonomously communicate (with one or moredevices of the wireless communications system 200) using resources ofthe grant-free configuration. The UE 115-a, however, may still receivegrants for other sets of resources (e.g., time-frequency resources thatdo not overlap with the resources indicated by the grant-freeconfiguration).

In the wireless communications system 200, the UE 115-a may embedinformation within an SR 205 that the base station 105-a may use toidentify whether the SR 205 is associated with a grant-free uplinkconfiguration, and if the SR 205 is associated with a grant-free uplinkconfiguration, the particular grant-free uplink configuration of a setof grant-free uplink configurations with which to associate the SR 205.That is, the UE 115-a may either convey with the SR 205 that the SR 205is not associated with any grant-free uplink configuration, or that theSR 205 is associated with a grant-free uplink configuration and the RAT,carrier, and grant-free uplink configuration indices with which the SRis associated. The grant-free uplink configuration may identifygrant-free resources on which the UE 115-a may transmit the uplinktransmission 210, and thus the resources for the base station 105-a todecode.

The grant-free uplink configuration information may be signaled using avariety of techniques. For example, the UE 115-a may transmit the SR 205using one of a set of different spreading sequences, where eachspreading sequence of the set corresponds to a respective grant-freeuplink configuration. Additionally or alternatively, the UE 115-a maytransmit the information using a codeword indicating the grant-freeuplink configuration (e.g., using a simplex code or a Reed Muller code).Additionally or alternatively, the UE 115-a may transmit the SR 205using one of a set of CRC masks, where each CRC mask of the setcorresponds to a respective grant-free uplink configuration. That is,according to each of these techniques, the UE 115-a may determine agrant-free uplink configuration and then apply the respective spreadingsequence, codeword, or CRC mask corresponding to the grant-free uplinkconfiguration.

When the base station 105-a receives the SR 205 according to thesetechniques, the base station 105-a may identify one or more grant-freeuplink configurations with which the SR 205 is associated, andaccordingly may determine which particular resources to decode (i.e.,the resources on which the UE 115-a transmitted the uplink transmission210). For example, the base station 105-a may identify that the SR isnot associated with a grant-free transmission and may transmit an uplinkgrant that indicates a set of resources for the UE to use for an uplinktransmission. In other examples, the base station 105-a may determinethat the SR is associated with a grant-free uplink transmission and theSR may indicate the grant-free configuration associated with thegrant-free uplink transmission. For instance, the SR may indicate thecarrier or a grant-free configuration index associated with thegrant-free uplink transmission. This information may indicate the set oftime-frequency resources that the base station 105-a is to monitor inorder to receive the grant-free uplink transmission associated with theSR.

The base station 105-a may further determine whether to transmit anuplink grant 215 to the UE 115-a. For example, if the base station 105-adetects and successfully decodes the uplink transmission 210 with whichthe SR 205 is associated, the base station 105-a may not transmit theuplink grant 215. Alternatively, if the base station 105-a does notsuccessfully decode the uplink transmission 210 with which the SR 205 isassociated, the base station 105-a may transmit the uplink grant 215 tothe UE 115-a. The uplink grant 215 may indicate a resource allocationthat the UE 115-a may use for subsequent transmissions or to retransmitthe data in the uplink transmission 210 that was not successfullydecoded. Additionally or alternatively, if the base station 105-a doesnot successfully decode the uplink transmission 210 with which the SR205 is associated, the base station 105-a may transmit a feedbackmessage (e.g., a negative acknowledgement (NACK)) to the UE 115-a, basedon which the UE 115-a may either retransmit the SR 205 or the uplinktransmission 210 (e.g., using different frequency-time resources).

Thus, when the UE 115-a is configured with multiple grant-free uplinkconfigurations, according to the described technique, the UE 115-a maybe able to indicate which particular grant-free uplink configuration ofa set of grant-free uplink configurations is used. In particular, thistechnique may be used across different carriers and RATs. For example,the UE 115-a may transmit the grant-free uplink transmission 210 on afirst carrier or using a first RAT and transmit the SR 205 on a secondcarrier or using a second RAT. In some cases, the UE 115-a may transmitthe SR 205 using a carrier or RAT with a relatively higher reliability,or that may provide a higher probability that the SR 205 is detected bythe base station 105-a (e.g., a carrier or RAT that uses a lower radiofrequency spectrum band as compared to the carrier or RAT used for theuplink transmission 210).

FIG. 3 illustrates an example of a process flow 300 in a wirelesscommunications system in accordance with aspects of the presentdisclosure. The process flow 300 includes a UE 115-b and a base station105-b, which may be respective examples of a UE 115 and a base station105 as described with reference to FIGS. 1 and 2. The process flow 300may be an example of the UE 115-b embedding information within an SRthat the base station 105-b may use to identify whether the SR isassociated with a grant-free uplink configuration, and if the SR isassociated with a grant-free uplink configuration, the particulargrant-free uplink configuration of a set of grant-free uplinkconfigurations with which to associate the SR. The operations in theprocess flow 300 performed by UE 115-b and base station 105-b may berespectively performed by either a UE 115 or a base station 105, and theexample shown should not be construed as limiting. In alternativeexamples, the operations shown as performed by UE 115-b may be performedby a base station 105, and the operations shown as performed by basestation 105-b may be performed by a UE 115. Similarly, the grant-freeconfigurations may be described with reference to grant-free uplinkconfiguration, but it should be understood that analogous operations maybe applied for the downlink.

At 305, the base station 105-b may identify a set of grant-freeconfigurations (e.g., grant-free uplink configurations). At 310, thebase station 105-b may transmit to the UE 115-b, and the UE 115-b mayreceive from the base station 105-b, a message that indicatesinformation that the UE 115-b may convey via SR. For example, the basestation 105-b may transmit the set of identified grant-freeconfigurations to the UE 115-b. The information may, for example, betransmitted in an RRC message or a MAC control element (CE) thatindicates information to convey via the SR. The signaling at 310 may, insome cases, be optional. For instance, the wireless communicationssystem supporting communications between UE 115-b and base station 105-bmay have previously configured the set of grant-free configurations orthe mechanism with which the UE 115-b is to embed information within anSR (e.g., spreading sequence, a codeword, CRC mask). In some aspects,the UE 115-b may be preconfigured with this information (e.g., based ona set of regulatory standards).

At 315, the UE 115-b may generate an SR for a set of data for an uplinktransmission from the UE 115-b to the base station 105-b.

At 320, the UE 115-b may determine whether the SR for the set of data,as may have been generated at 315, is associated with a grant-freeconfiguration for the UE 115-b. In the case that the SR is forassociated with the grant-free configuration for the UE 115-b, the UE115-b may identify a set of resources (e.g., time-frequency resources)for the uplink transmission based on the grant-free configuration.

At 325, the UE 115-b may transmit to the base station 105-b, and thebase station 105-b may receive from the UE 115-b, an indication ofwhether the SR is associated with the grant-free configuration based onthe determination at 320. Transmitting the indication may includetransmitting the SR to the base station 105-b, as may have beengenerated at 315, where the SR indicates whether the SR is associatedwith the grant-free configuration. In some cases, the SR may indicatethat the SR is associated with the grant-free configuration, and the SRindicates a RAT, a carrier, an index of the grant-free configuration, ora combination (i.e., a carrier or bearer index for the uplinktransmission at 335). Alternatively, the SR may indicate that the SR isnot associated with a grant-free configuration.

In some cases, transmitting the SR may include identifying a spreadingsequence that indicates information associated with the grant-freeconfiguration and transmitting the SR according to the spreadingsequence. Additionally or alternatively, transmitting the SR may includeidentifying a codeword that indicates information associated with thegrant-free configuration and transmitting the SR including the codeword.Additionally or alternatively, transmitting the SR may includeidentifying a CRC mask corresponding to information associated with thegrant-free configuration and transmitting the SR based on the CRC mask.

At 330, the base station 105-b may determine whether the SR isassociated with a grant-free configuration. If, for example, the SR isassociated with a grant-free configuration, the base station 105-b mayidentify the spreading sequence associated with the SR, where thespreading sequence indicates information associated with the grant-freeconfiguration. Additionally or alternatively, the base station 105-b mayidentify the codeword of the SR, where the codeword indicatesinformation associated with the grant-free configuration. Additionallyor alternatively, the base station 105-b may determine a CRC mask of theSR, where the CRC mask corresponds to information associated with thegrant-free configuration.

At 335, the UE 115-b may transmit to the base station 105-b, and thebase station 105-b may receive from the UE 115-b, the uplinktransmission. The UE 115-b may transmit the uplink transmission via theset of resources as may have been identified at 320. In some cases, theuplink transmission and the SR, as may have been transmitted at 325, maybe transmitted on different carriers or using different RATs.

At 340, the base station 105-b may, for example, if the base station105-b determines at 330 that the SR is associated with the grant-freeconfiguration, decode the set of resources. The set of resources mayinclude the uplink transmission, as may have been received at 335.

At 345, the base station 105-b may transmit to the UE 115-b, and the UE115-b may receive from the base station 105-b, a downlink transmissionbased on the SR, as may have been received at 325. The downlinktransmission may include a feedback message, an uplink grant, or acombination. In the case in which the SR is not associated with thegrant-free configuration for the UE 115-b, the downlink transmission mayinclude a grant (e.g., an uplink grant) that indicates a set ofresources (e.g., time-frequency resources) for the uplink transmission.

At 350, the UE 115-b may transmit to the base station 105-b, and thebase station 105-b may receive from the UE 115-b, an uplinktransmission. The uplink transmission at 350 may, for example, be aretransmission of the data that may have been transmitted in the uplinktransmission at 335. The UE 115-b may transmit the uplink transmissionusing the set of time-frequency resources as may have been indicated bythe base station 105-b via the downlink transmission at 345.

FIG. 4 shows a block diagram 400 of a device 405 in accordance withaspects of the present disclosure. The device 405 may be an example ofaspects of a UE 115 as described herein. The device 405 may include areceiver 410, a communications manager 415, and a transmitter 420. Thedevice 405 may also include a processor. Each of these components may bein communication with one another (e.g., via one or more buses).

The receiver 410 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to schedulingrequests for grant-free configurations, etc.). Information may be passedon to other components of the device 405. The receiver 410 may be anexample of aspects of the transceiver 720 described with reference toFIG. 7. The receiver 410 may utilize a single antenna or a set ofantennas.

The communications manager 415 may generate an SR for a set of data foran uplink transmission from a UE to a base station, determine whetherthe SR for the set of data is associated with a grant-free configurationfor the UE, and transmit, to the base station, an indication of whetherthe SR is associated with the grant-free configuration based on thedetermination. The communications manager 415 may be an example ofaspects of the communications manager 710 described herein.

The communications manager 415, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 415, or itssub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The communications manager 415, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 415, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 415, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

The transmitter 420 may transmit signals generated by other componentsof the device 405. In some examples, the transmitter 420 may becollocated with a receiver 410 in a transceiver module. For example, thetransmitter 420 may be an example of aspects of the transceiver 720described with reference to FIG. 7. The transmitter 420 may utilize asingle antenna or a set of antennas.

FIG. 5 shows a block diagram 500 of a device 505 in accordance withaspects of the present disclosure. The device 505 may be an example ofaspects of a device 405 or a UE 115 as described herein. The device 505may include a receiver 510, a communications manager 515, and atransmitter 530. The device 505 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 510 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to schedulingrequests for grant-free configurations, etc.). Information may be passedon to other components of the device 505. The receiver 510 may be anexample of aspects of the transceiver 720 described with reference toFIG. 7. The receiver 510 may utilize a single antenna or a set ofantennas.

The communications manager 515 may be an example of aspects of thecommunications manager 415 as described herein. The communicationsmanager 515 may include an SR manager 520 and a grant-free configurationmanager 525. The communications manager 515 may be an example of aspectsof the communications manager 710 described herein.

The SR manager 520 may generate an SR for a set of data for an uplinktransmission from a UE 115 to a base station 105.

The grant-free configuration manager 525 may determine whether the SRfor the set of data is associated with a grant-free configuration forthe UE 115 and transmit, to the base station 105, an indication ofwhether the SR is associated with the grant-free configuration based onthe determination.

The transmitter 530 may transmit signals generated by other componentsof the device 505. In some examples, the transmitter 530 may becollocated with a receiver 510 in a transceiver module. For example, thetransmitter 530 may be an example of aspects of the transceiver 720described with reference to FIG. 7. The transmitter 530 may utilize asingle antenna or a set of antennas.

FIG. 6 shows a block diagram 600 of a communications manager 605 inaccordance with aspects of the present disclosure. The communicationsmanager 605 may be an example of aspects of a communications manager415, a communications manager 515, or a communications manager 710described herein. The communications manager 605 may include an SRmanager 610, a grant-free configuration manager 615, a spreadingsequence component 620, a codeword component 625, a CRC component 630,and an uplink transmission manager 635. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

The SR manager 610 may generate an SR for a set of data for an uplinktransmission from a UE 115 to a base station 105. In some examples, theSR manager 610 may transmit the SR to the base station 105, where the SRindicates whether the SR is associated with the grant-freeconfiguration. In some examples, the SR manager 610 may transmit the SRaccording to a spreading sequence. In some examples, transmitting the SRincluding a codeword. In some examples, the SR manager 610 may transmitthe SR based on a CRC mask.

In some examples, the SR manager 610 may transmit the SR to the basestation 105, where the SR is not associated with the grant-freeconfiguration for the UE 115. Alternatively, the SR manager 610 maytransmit the SR to the base station 105, where the SR is associated withthe grant-free configuration for the UE 115. In some cases, the SRindicates that the SR is associated with the grant-free configuration.In some cases, the SR indicates a RAT, a carrier, an index of thegrant-free configuration, or a combination. In some cases, the SRindicates that the SR is not associated with the grant-freeconfiguration.

The grant-free configuration manager 615 may determine whether the SRfor the set of data is associated with a grant-free configuration forthe UE 115. In some examples, the grant-free configuration manager 615may transmit, to the base station 105, an indication of whether the SRis associated with the grant-free configuration based on thedetermination.

In some examples, the grant-free configuration manager 615 may identifya set of time-frequency resources based on the grant-free configuration.

The spreading sequence component 620 may identify the spreading sequencethat indicates information associated with the grant-free configuration.

The codeword component 625 may identify the codeword that indicatesinformation associated with the grant-free configuration.

The CRC component 630 may identify the CRC mask corresponding toinformation associated with the grant-free configuration.

The uplink transmission manager 635 may receive, from the base station105, a grant that indicates a set of time-frequency resources for theuplink transmission. In some examples, the uplink transmission manager635 may transmit the uplink transmission to the base station via the setof time-frequency resources. In some cases, the uplink transmission andthe SR are transmitted on different carriers. In some cases, the uplinktransmission and the SR are transmitted using different RATs.

FIG. 7 shows a diagram of a system 700 including a device 705 inaccordance with aspects of the present disclosure. The device 705 may bean example of or include the components of device 405, device 505, or aUE 115 as described herein. The device 705 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a communicationsmanager 710, an I/O controller 715, a transceiver 720, an antenna 725,memory 730, and a processor 740. These components may be in electroniccommunication via one or more buses (e.g., bus 745).

The communications manager 710 may generate an SR for a set of data foran uplink transmission from a UE 115 to a base station 105 and determinewhether the SR for the set of data is associated with a grant-freeconfiguration for the UE 115. The communications manager 710 maygenerate transmit, to the base station 105, an indication of whether theSR is associated with the grant-free configuration based on thedetermination.

The I/O controller 715 may manage input and output signals for thedevice 705. The I/O controller 715 may also manage peripherals notintegrated into the device 705. In some cases, the I/O controller 715may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 715 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 715may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 715may be implemented as part of a processor. In some cases, a user mayinteract with the device 705 via the I/O controller 715 or via hardwarecomponents controlled by the I/O controller 715.

The transceiver 720 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 720 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 720may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas.

In some cases, the device 705 may include a single antenna 725 or, insome cases, the device 705 may have more than one antenna 725, which maybe capable of concurrently transmitting or receiving multiple wirelesstransmissions.

The memory 730 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 730 may store computer-readable,computer-executable code 735 including instructions that, when executed,cause the processor to perform various functions described herein. Insome cases, the memory 730 may contain, among other things, a Basic I/OSystem (BIOS) which may control basic hardware or software operationsuch as the interaction with peripheral components or devices.

The processor 740 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 740 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 740. The processor 740 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 730) to cause the device 705 to perform variousfunctions (e.g., functions or tasks supporting scheduling requests forgrant-free configurations).

The code 735 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 735 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 735 may not be directly executable by theprocessor 740 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 8 shows a block diagram 800 of a device 805 in accordance withaspects of the present disclosure. The device 805 may be an example ofaspects of a base station 105 as described herein. The device 805 mayinclude a receiver 810, a communications manager 815, and a transmitter820. The device 805 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

The receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to schedulingrequests for grant-free configurations, etc.). Information may be passedon to other components of the device 805. The receiver 810 may be anexample of aspects of the transceiver 1120 described with reference toFIG. 11. The receiver 810 may utilize a single antenna or a set ofantennas.

The communications manager 815 may identify, by a base station, a set ofgrant-free configurations for a UE, receive, from the UE, an SRassociated with an uplink transmission from the UE to the base station,where the SR indicates whether the SR is associated with a grant-freeconfiguration of the set of grant-free configurations, and transmit adownlink transmission to the UE based on the SR, where the downlinktransmission includes a feedback message, an uplink grant, or acombination thereof. The communications manager 815 may be an example ofaspects of the communications manager 1110 described herein.

The communications manager 815, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 815, or itssub-components may be executed by a general-purpose processor, a DSP, anASIC, an FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The communications manager 815, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 815, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 815, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an I/O component, a transceiver, a network server,another computing device, one or more other components described in thepresent disclosure, or a combination thereof in accordance with variousaspects of the present disclosure.

The transmitter 820 may transmit signals generated by other componentsof the device 805. In some examples, the transmitter 820 may becollocated with a receiver 810 in a transceiver module. For example, thetransmitter 820 may be an example of aspects of the transceiver 1120described with reference to FIG. 11. The transmitter 820 may utilize asingle antenna or a set of antennas.

FIG. 9 shows a block diagram 900 of a device 905 in accordance withaspects of the present disclosure. The device 905 may be an example ofaspects of a device 805 or a base station 105 as described herein. Thedevice 905 may include a receiver 910, a communications manager 915, anda transmitter 935. The device 905 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to schedulingrequests for grant-free configurations, etc.). Information may be passedon to other components of the device 905. The receiver 910 may be anexample of aspects of the transceiver 1120 described with reference toFIG. 11. The receiver 910 may utilize a single antenna or a set ofantennas.

The communications manager 915 may be an example of aspects of thecommunications manager 815 as described herein. The communicationsmanager 915 may include a grant-free configuration manager 920, an SRmanager 925, and a downlink transmission manager 930. The communicationsmanager 915 may be an example of aspects of the communications manager1110 described herein.

The grant-free configuration manager 920 may identify, by a base station105, a set of grant-free configurations for a UE.

The SR manager 925 may receive, from the UE 115, an SR associated withan uplink transmission from the UE 115 to the base station 105, wherethe SR indicates whether the SR is associated with a grant-freeconfiguration of the set of grant-free configurations.

The downlink transmission manager 930 may transmit a downlinktransmission to the UE 115 based on the SR, where the downlinktransmission includes a feedback message, an uplink grant, or acombination thereof.

The transmitter 935 may transmit signals generated by other componentsof the device 905. In some examples, the transmitter 935 may becollocated with a receiver 910 in a transceiver module. For example, thetransmitter 935 may be an example of aspects of the transceiver 1120described with reference to FIG. 11. The transmitter 935 may utilize asingle antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a communications manager 1005 inaccordance with aspects of the present disclosure. The communicationsmanager 1005 may be an example of aspects of a communications manager815, a communications manager 915, or a communications manager 1110described herein. The communications manager 1005 may include agrant-free configuration manager 1010, an SR manager 1015, a downlinktransmission manager 1020, a decoder component 1025, a spreadingsequence component 1030, a codeword component 1035, a CRC component1040, and an uplink transmission receiver 1045. Each of these modulesmay communicate, directly or indirectly, with one another (e.g., via oneor more buses).

The grant-free configuration manager 1010 may identify, by a basestation, a set of grant-free configurations for a UE 115. In someexamples, the grant-free configuration manager 1010 may determine thatthe SR is associated with the grant-free configuration. Alternatively,the grant-free configuration manager 1010 may determine that the SR isnot associated with the grant-free configuration.

The SR manager 1015 may receive, from the UE 115, an SR associated withan uplink transmission from the UE to the base station, where the SRindicates whether the SR is associated with a grant-free configurationof the set of grant-free configurations. In some examples, the SRmanager 1015 may transmit, to the UE 115, an RRC message or a MAC CEthat indicates information to convey via the SR. In some cases, the SRindicates a RAT, a carrier, an index of the grant-free configuration, ora combination.

The downlink transmission manager 1020 may transmit a downlinktransmission to the UE 115 based on the SR, where the downlinktransmission includes a feedback message, an uplink grant, or acombination thereof. In some examples, the downlink transmission manager1020 may transmit the feedback message or the uplink grant based ondetermining that the SR is not associated with the grant-freeconfiguration.

The decoder component 1025 may decode a transmission from the UEtransmitted over a set of time-frequency resources associated with thegrant-free configuration.

The spreading sequence component 1030 may identify a spreading sequenceassociated with the SR, where the spreading sequence indicatesinformation associated with the grant-free configuration.

The codeword component 1035 may identify a codeword of the SR, where thecodeword indicates information associated with the grant-freeconfiguration.

The CRC component 1040 may determine a CRC mask of the SR, where the CRCmask corresponds to information associated with the grant-freeconfiguration.

The uplink transmission receiver 1045 may receive the uplinktransmission from the UE based on the SR. In some cases, the uplinktransmission and the SR are received on different carriers. In somecases, the uplink transmission and the SR are received using differentRATs.

FIG. 11 shows a diagram of a system 1100 including a device 1105 inaccordance with aspects of the present disclosure. The device 1105 maybe an example of or include the components of device 805, device 905, ora base station 105 as described herein. The device 1105 may includecomponents for bi-directional voice and data communications includingcomponents for transmitting and receiving communications, including acommunications manager 1110, a network communications manager 1115, atransceiver 1120, an antenna 1125, memory 1130, a processor 1140, and aninter-station communications manager 1145. These components may be inelectronic communication via one or more buses (e.g., bus 1150).

The communications manager 1110 may identify, by a base station 105, aset of grant-free configurations for a UE 115. The communicationsmanager 1110 may receive, from the UE 115, an SR associated with anuplink transmission from the UE 115 to the base station 105, where theSR indicates whether the SR is associated with a grant-freeconfiguration of the set of grant-free configurations. Thecommunications manager 1110 may transmit a downlink transmission to theUE 115 based on the SR, where the downlink transmission may include afeedback message, an uplink grant, or a combination thereof.

The network communications manager 1115 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1115 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1120 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1120 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1120 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the device 1105 may include a single antenna 1125, or, insome cases, the device 1105 may have more than one antenna 1125, whichmay be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1130 may include RAM, ROM, or a combination thereof. Thememory 1130 may store computer-readable code 1135 including instructionsthat, when executed by a processor (e.g., the processor 1140) cause thedevice to perform various functions described herein. In some cases, thememory 1130 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1140 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1140 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1140. The processor 1140 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1130) to cause the device #{device} to perform various functions(e.g., functions or tasks supporting scheduling requests for grant-freeconfigurations).

The inter-station communications manager 1145 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1145 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1145 may provide an X2 interface within an LTE/LTE-A wirelesscommunications network technology to provide communication between basestations 105.

The code 1135 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1135 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1135 may not be directly executable by theprocessor 1140 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 12 shows a flowchart illustrating a method 1200 in accordance withaspects of the present disclosure. The operations of method 1200 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1200 may be performed by acommunications manager as described with reference to FIGS. 4 through 7.In some examples, a UE 115 may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedbelow. Additionally or alternatively, a UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At 1205, a UE 115 may generate an SR for a set of data for an uplinktransmission from the UE 115 to a base station 105. The operations of1205 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1205 may be performed by an SRmanager as described with reference to FIGS. 4 through 7.

At 1210, the UE 115 may determine whether the SR for the set of data isassociated with a grant-free configuration for the UE 115. Theoperations of 1210 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1210 may beperformed by a grant-free configuration manager as described withreference to FIGS. 4 through 7.

At 1215, the UE 115 may transmit, to the base station 105, an indicationof whether the SR is associated with the grant-free configuration basedon the determination. The operations of 1215 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1215 may be performed by a grant-free configurationmanager as described with reference to FIGS. 4 through 7.

FIG. 13 shows a flowchart illustrating a method 1300 in accordance withaspects of the present disclosure. The operations of method 1300 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1300 may be performed by acommunications manager as described with reference to FIGS. 4 through 7.In some examples, a UE 115 may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedbelow. Additionally or alternatively, a UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At 1305, a UE 115 may generate an SR for a set of data for an uplinktransmission from the UE 115 to a base station 105. The operations of1305 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1305 may be performed by an SRmanager as described with reference to FIGS. 4 through 7.

At 1310, the UE 115 may determine whether the SR for the set of data isassociated with a grant-free configuration for the UE 115. Theoperations of 1310 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1310 may beperformed by a grant-free configuration manager as described withreference to FIGS. 4 through 7.

At 1315, the UE 115 may transmit the SR to the base station 105, wherethe SR indicates whether the SR is associated with the grant-freeconfiguration. The operations of 1315 may be performed according to themethods described herein. In some examples, aspects of the operations of1315 may be performed by an SR manager as described with reference toFIGS. 4 through 7.

At 1320, the UE 115 may transmit, to the base station 105, an indicationof whether the SR is associated with the grant-free configuration basedon the determination. The operations of 1320 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1320 may be performed by a grant-free configurationmanager as described with reference to FIGS. 4 through 7.

FIG. 14 shows a flowchart illustrating a method 1400 in accordance withaspects of the present disclosure. The operations of method 1400 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1400 may be performed by acommunications manager as described with reference to FIGS. 4 through 7.In some examples, a UE 115 may execute a set of instructions to controlthe functional elements of the UE 115 to perform the functions describedbelow. Additionally or alternatively, a UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At 1405, a UE 115 may generate an SR for a set of data for an uplinktransmission from the UE 115 to a base station 105. The operations of1405 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1405 may be performed by an SRmanager as described with reference to FIGS. 4 through 7.

At 1410, the UE 115 may determine whether the SR for the set of data isassociated with a grant-free configuration for the UE 115. Theoperations of 1410 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1410 may beperformed by a grant-free configuration manager as described withreference to FIGS. 4 through 7.

At 1415, the UE 115 may transmit, to the base station 105, an indicationof whether the SR is associated with the grant-free configuration basedon the determination. The operations of 1415 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1415 may be performed by a grant-free configurationmanager as described with reference to FIGS. 4 through 7.

At 1420, the UE 115 may transmit the SR to the base station 105, wherethe SR is not associated with the grant-free configuration for the UE115. The operations of 1420 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1420may be performed by an SR manager as described with reference to FIGS. 4through 7.

At 1425, the UE 115 may receive, from the base station, a grant thatindicates a set of time-frequency resources for the uplink transmission.The operations of 1425 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1425may be performed by an uplink transmission manager as described withreference to FIGS. 4 through 7.

At 1430, the UE 115 may transmit the uplink transmission to the basestation 105 via the set of time-frequency resources. The operations of1430 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1430 may be performed by anuplink transmission manager as described with reference to FIGS. 4through 7.

FIG. 15 shows a flowchart illustrating a method 1500 in accordance withaspects of the present disclosure. The operations of method 1500 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1500 may be performed by acommunications manager as described with reference to FIGS. 4 through 7.In some examples, a UE 115 may execute a set of instructions to controlthe functional elements of the UE to perform the functions describedbelow. Additionally or alternatively, a UE 115 may perform aspects ofthe functions described below using special-purpose hardware.

At 1505, a UE 115 may generate an SR for a set of data for an uplinktransmission from the UE 115 to a base station 105. The operations of1505 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1505 may be performed by an SRmanager as described with reference to FIGS. 4 through 7.

At 1510, the UE 115 may determine whether the SR for the set of data isassociated with a grant-free configuration for the UE 115. Theoperations of 1510 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1510 may beperformed by a grant-free configuration manager as described withreference to FIGS. 4 through 7.

At 1515, the UE 115 may transmit the SR to the base station 105, wherethe SR may be associated with the grant-free configuration for the UE115. The operations of 1515 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1515may be performed by an SR manager as described with reference to FIGS. 4through 7.

At 1520, the UE 115 may transmit, to the base station 105, an indicationof whether the SR is associated with the grant-free configuration basedon the determination. The operations of 1520 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1520 may be performed by a grant-free configurationmanager as described with reference to FIGS. 4 through 7.

At 1525, the UE 115 may identify a set of time-frequency resources basedon the grant-free configuration. The operations of 1525 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1525 may be performed by a grant-free configurationmanager as described with reference to FIGS. 4 through 7.

At 1530, the UE 115 may transmit the uplink transmission to the basestation via the set of time-frequency resources. The operations of 1530may be performed according to the methods described herein. In someexamples, aspects of the operations of 1530 may be performed by anuplink transmission manager as described with reference to FIGS. 4through 7.

FIG. 16 shows a flowchart illustrating a method 1600 in accordance withaspects of the present disclosure. The operations of method 1600 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1600 may be performed by acommunications manager as described with reference to FIGS. 8 through11. In some examples, a base station 105 may execute a set ofinstructions to control the functional elements of the base station 105to perform the functions described below. Additionally or alternatively,a base station 105 may perform aspects of the functions described belowusing special-purpose hardware.

At 1605, a base station may identify a set of grant-free configurationsfor a UE 115. The operations of 1605 may be performed according to themethods described herein. In some examples, aspects of the operations of1605 may be performed by a grant-free configuration manager as describedwith reference to FIGS. 8 through 11.

At 1610, the base station 105 may receive, from the UE 115, an SRassociated with an uplink transmission from the UE 115 to the basestation 105, where the SR indicates whether the SR is associated with agrant-free configuration of the set of grant-free configurations. Theoperations of 1610 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1610 may beperformed by an SR manager as described with reference to FIGS. 8through 11.

At 1615, the base station 105 may transmit a downlink transmission tothe UE 115 based on the SR, where the downlink transmission may includea feedback message, an uplink grant, or a combination thereof. Theoperations of 1615 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1615 may beperformed by a downlink transmission manager as described with referenceto FIGS. 8 through 11.

FIG. 17 shows a flowchart illustrating a method 1700 in accordance withaspects of the present disclosure. The operations of method 1700 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1700 may be performed by acommunications manager as described with reference to FIGS. 8 through11. In some examples, a base station 105 may execute a set ofinstructions to control the functional elements of the base station toperform the functions described below. Additionally or alternatively, abase station 105 may perform aspects of the functions described belowusing special-purpose hardware.

At 1705, a base station 105 may identify a set of grant-freeconfigurations for a UE 115. The operations of 1705 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1705 may be performed by a grant-free configurationmanager as described with reference to FIGS. 8 through 11.

At 1710, the base station 105 may receive, from the UE, an SR associatedwith an uplink transmission from the UE 115 to the base station 105,where the SR indicates whether the SR is associated with a grant-freeconfiguration of the set of grant-free configurations. The operations of1710 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1710 may be performed by an SRmanager as described with reference to FIGS. 8 through 11.

At 1715, the base station 105 may determine that the SR is associatedwith the grant-free configuration. The operations of 1715 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1715 may be performed by a grant-freeconfiguration manager as described with reference to FIGS. 8 through 11.

At 1720, the base station 105 may decode a transmission from the UEtransmitted over a set of time-frequency resources associated with thegrant-free configuration. The operations of 1720 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1720 may be performed by a decoder component asdescribed with reference to FIGS. 8 through 11.

At 1725, the base station 105 may transmit a downlink transmission tothe UE 115 based on the SR, where the downlink transmission may includea feedback message, an uplink grant, or a combination thereof. Theoperations of 1725 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1725 may beperformed by a downlink transmission manager as described with referenceto FIGS. 8 through 11.

FIG. 18 shows a flowchart illustrating a method 1800 in accordance withaspects of the present disclosure. The operations of method 1800 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1800 may be performed by acommunications manager as described with reference to FIGS. 8 through11. In some examples, a base station 105 may execute a set ofinstructions to control the functional elements of the base station 105to perform the functions described below. Additionally or alternatively,a base station 105 may perform aspects of the functions described belowusing special-purpose hardware.

At 1805, the base station 105 may identify a set of grant-freeconfigurations for a UE 115. The operations of 1805 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1805 may be performed by a grant-free configurationmanager as described with reference to FIGS. 8 through 11.

At 1810, the base station 105 may receive, from the UE 115, an SRassociated with an uplink transmission from the UE 115 to the basestation 105, where the SR indicates whether the SR is associated with agrant-free configuration of the set of grant-free configurations. Theoperations of 1810 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1810 may beperformed by an SR manager as described with reference to FIGS. 8through 11.

At 1815, the base station 105 may transmit a downlink transmission tothe UE 115 based on the SR, where the downlink transmission may includea feedback message, an uplink grant, or a combination thereof. Theoperations of 1815 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1815 may beperformed by a downlink transmission manager as described with referenceto FIGS. 8 through 11.

At 1820, the base station 105 may determine that the SR is notassociated with the grant-free configuration. The operations of 1820 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1820 may be performed by agrant-free configuration manager as described with reference to FIGS. 8through 11.

At 1825, the base station 105 may transmit the feedback message or theuplink grant based on determining that the SR is not associated with thegrant-free configuration. The operations of 1825 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1825 may be performed by a downlink transmissionmanager as described with reference to FIGS. 8 through 11.

FIG. 19 shows a flowchart illustrating a method 1900 in accordance withaspects of the present disclosure. The operations of method 1900 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1900 may be performed by acommunications manager as described with reference to FIGS. 8 through11. In some examples, a base station 105 may execute a set ofinstructions to control the functional elements of the base station 105to perform the functions described below. Additionally or alternatively,a base station 105 may perform aspects of the functions described belowusing special-purpose hardware.

At 1905, the base station 105 may identify a set of grant-freeconfigurations for a UE 115. The operations of 1905 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1905 may be performed by a grant-free configurationmanager as described with reference to FIGS. 8 through 11.

At 1910, the base station 105 may receive, from the UE 115, an SRassociated with an uplink transmission from the UE 115 to the basestation 105, where the SR indicates whether the SR is associated with agrant-free configuration of the set of grant-free configurations. Theoperations of 1910 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1910 may beperformed by an SR manager as described with reference to FIGS. 8through 11.

At 1915, the base station 105 may receive the uplink transmission fromthe UE 115 based on the SR. The operations of 1915 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1915 may be performed by an uplink transmissionreceiver as described with reference to FIGS. 8 through 11.

At 1920, the base station 105 may transmit a downlink transmission tothe UE 115 based on the SR, where the downlink transmission may includea feedback message, an uplink grant, or a combination thereof. Theoperations of 1920 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1920 may beperformed by a downlink transmission manager as described with referenceto FIGS. 8 through 11.

It should be noted that the methods described above describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code-division multiple access (CDMA),time-division multiple access (TDMA), frequency-division multiple access(FDMA), orthogonal frequency-division multiple access (OFDMA), singlecarrier frequency-division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), E-UTRA, Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20,Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider. A small cellmay be associated with a lower-powered base station 105, as comparedwith a macro cell, and a small cell may operate in the same or different(e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Smallcells may include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs 115 with servicesubscriptions with the network provider. A femto cell may also cover asmall geographic area (e.g., a home) and may provide restricted accessby UEs 115 having an association with the femto cell (e.g., UEs 115 in aclosed subscriber group (CSG), UEs 115 for users in the home, and thelike). An eNB for a macro cell may be referred to as a macro eNB. An eNBfor a small cell may be referred to as a small cell eNB, a pico eNB, afemto eNB, or a home eNB. An eNB may support one or multiple (e.g., two,three, four, and the like) cells, and may also support communicationsusing one or multiple component carriers.

The wireless communications systems 100 and 200, or systems describedherein may support synchronous or asynchronous operation. Forsynchronous operation, the base stations 105 may have similar frametiming, and transmissions from different base stations 105 may beapproximately aligned in time. For asynchronous operation, the basestations 105 may have different frame timing, and transmissions fromdifferent base stations 105 may not be aligned in time. The techniquesdescribed herein may be used for either synchronous or asynchronousoperations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communications, comprising:generating a scheduling request (SR) for a set of data for an uplinktransmission from a user equipment (UE) to a base station; determiningwhether the SR for the set of data is associated with a grant-freeconfiguration for the UE; and transmitting, to the base station, anindication of whether the SR is associated with the grant-freeconfiguration based at least in part on the determination.
 2. The methodof claim 1, wherein transmitting the indication comprises: transmittingthe SR to the base station, wherein the SR indicates whether the SR isassociated with the grant-free configuration.
 3. The method of claim 2,wherein transmitting the SR comprises: identifying a spreading sequencethat indicates information associated with the grant-free configuration;and transmitting the SR according to the spreading sequence.
 4. Themethod of claim 2, further comprising: identifying a codeword thatindicates information associated with the grant-free configuration; andtransmitting the SR, wherein the SR comprises the codeword.
 5. Themethod of claim 2, further comprising: identifying a cyclic redundancycheck (CRC) mask corresponding to information associated with thegrant-free configuration; and transmitting the SR based at least in parton the CRC mask.
 6. The method of claim 2, wherein: the SR indicatesthat the SR is associated with the grant-free configuration; and the SRindicates a radio-access technology (RAT), a carrier, an index of thegrant-free configuration, or a combination thereof.
 7. The method ofclaim 2, wherein the SR indicates that the SR is not associated with thegrant-free configuration.
 8. The method of claim 1, further comprising:transmitting the SR to the base station, wherein the SR is notassociated with the grant-free configuration for the UE; receiving, fromthe base station, a grant that indicates a set of time-frequencyresources for the uplink transmission; and transmitting the uplinktransmission to the base station via the set of time-frequencyresources.
 9. The method of claim 1, further comprising: transmittingthe SR to the base station, wherein the SR is associated with thegrant-free configuration for the UE; identifying a set of time-frequencyresources based at least in part on the grant-free configuration; andtransmitting the uplink transmission to the base station via the set oftime-frequency resources.
 10. The method of claim 9, wherein the uplinktransmission and the SR are transmitted on different carriers.
 11. Themethod of claim 9, wherein the uplink transmission and the SR aretransmitted using different radio-access technologies (RATs).
 12. Amethod for wireless communications, comprising: identifying, by a basestation, a set of grant-free configurations for a user equipment (UE);receiving, from the UE, a scheduling request (SR) associated with anuplink transmission from the UE to the base station, wherein the SRindicates whether the SR is associated with a grant-free configurationof the set of grant-free configurations; and transmitting a downlinktransmission to the UE based at least in part on the SR, wherein thedownlink transmission comprises a feedback message, an uplink grant, ora combination thereof.
 13. The method of claim 12, further comprising:determining that the SR is associated with the grant-free configuration;and decoding a transmission from the UE transmitted over a set oftime-frequency resources associated with the grant-free configuration.14. The method of claim 13, further comprising: identifying a spreadingsequence associated with the SR, wherein the spreading sequenceindicates information associated with the grant-free configuration. 15.The method of claim 13, further comprising: identifying a codeword ofthe SR, wherein the codeword indicates information associated with thegrant-free configuration.
 16. The method of claim 13, furthercomprising: determining a cyclic redundancy check (CRC) mask of the SR,wherein the CRC mask corresponds to information associated with thegrant-free configuration.
 17. The method of claim 13, wherein the SRindicates a radio-access technologies (RATs), a carrier, an index of thegrant-free configuration, or a combination thereof.
 18. The method ofclaim 12, further comprising: transmitting, to the UE, a radio resourcecontrol (RRC) message or a media access control (MAC) control element(CE) that indicates information to convey via the SR.
 19. The method ofclaim 12, further comprising: determining that the SR is not associatedwith the grant-free configuration; and transmitting the feedback messageor the uplink grant based at least in part on determining that the SR isnot associated with the grant-free configuration.
 20. The method ofclaim 12, further comprising receiving the uplink transmission from theUE based at least in part on the SR.
 21. The method of claim 20, whereinthe uplink transmission and the SR are received on different carriers.22. The method of claim 20, wherein the uplink transmission and the SRare received using different radio-access technologies (RATs).
 23. Anapparatus for wireless communications, comprising: a processor, memoryin electronic communication with the processor; and instructions storedin the memory and executable by the processor to cause the apparatus to:generate a scheduling request (SR) for a set of data for an uplinktransmission from a user equipment (UE) to a base station; determinewhether the SR for the set of data is associated with a grant-freeconfiguration for the UE; and transmit, to the base station, anindication of whether the SR is associated with the grant-freeconfiguration based at least in part on the determination.
 24. Theapparatus of claim 23, wherein the instructions to transmit theindication are executable by the processor to cause the apparatus to:transmit the SR to the base station, wherein the SR indicates whetherthe SR is associated with the grant-free configuration.
 25. Theapparatus of claim 24, wherein the instructions to transmit the SR areexecutable by the processor to cause the apparatus to: identify aspreading sequence that indicates information associated with thegrant-free configuration; and transmit the SR according to the spreadingsequence.
 26. The apparatus of claim 24, wherein the instructions arefurther executable by the processor to cause the apparatus to: identifya codeword that indicates information associated with the grant-freeconfiguration; and transmit the SR, wherein the SR comprises thecodeword.
 27. An apparatus for wireless communications, comprising: aprocessor, memory in electronic communication with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to: identify, by a base station, a set of grant-freeconfigurations for a user equipment (UE); receive, from the UE, ascheduling request (SR) associated with an uplink transmission from theUE to the base station, wherein the SR indicates whether the SR isassociated with a grant-free configuration of the set of grant-freeconfigurations; and transmit a downlink transmission to the UE based atleast in part on the SR, wherein the downlink transmission comprises afeedback message, an uplink grant, or a combination thereof.
 28. Theapparatus of claim 27, wherein the instructions are further executableby the processor to cause the apparatus to: determine that the SR isassociated with the grant-free configuration; and decode a transmissionfrom the UE transmitted over a set of time-frequency resourcesassociated with the grant-free configuration.
 29. The apparatus of claim28, wherein the instructions are further executable by the processor tocause the apparatus to: identify a spreading sequence associated withthe SR, wherein the spreading sequence indicates information associatedwith the grant-free configuration.
 30. The apparatus of claim 28,wherein the instructions are further executable by the processor tocause the apparatus to: identify a codeword of the SR, wherein thecodeword indicates information associated with the grant-freeconfiguration.